In SQL 2000 where the role change was relatively easy through the use of stored procedures, unfortunately in SQL 2005 those SPs are no longer used and we have to perform the following steps to sync the secondary server with primary and then failover.

Log Shipping is one of the methods for creating a Standby server, by god forbidden if something happens to our production server we need a standby server and Microsoft has come up with this idea and introduced Log Shipping in SQL 2000 itself. But in SQL 2005 it has been enhanced further by making it more user friendly. It is mainly used in OLTP environment (Online Transaction Processing). It is used as a High Availability Solution and also in Disaster recovery situations.

Log shipping allows you to automatically send transaction log backups from one database (known as the primary database) to a secondary database on another server (known as the secondary server). At the secondary server, these transaction log backups are restored to the secondary database, keeping it closely synchronized with the primary database. An optional third server, known as the monitor server, records the history and status of backup and restores operations and optionally raises alerts if these operations fail to occur as scheduled.

Overview of Mirroring:

Mirroring is mainly implemented for increasing the database availability. Similar to log shipping mirroring is also implemented on per database basis. Database mirroring maintains two copies of a single database that must reside on different instances of SQL Server Database Engine (server instances). Typically, these server instances reside on computers in different locations. One server instance serves the database to clients (the principal server), while the other server instance acts as a hot or warm standby server (the mirror server).